Oswaldo Cruz Foundation

About: Oswaldo Cruz Foundation is a facility organization based out in Rio de Janeiro, Brazil. It is known for research contribution in the topics: Population & Trypanosoma cruzi. The organization has 18673 authors who have published 36752 publications receiving 802378 citations. The organization is also known as: Fundação Oswaldo Cruz & FIOCRUZ.

Vaccine-induced CD8 + T cells control AIDS virus replication

Abstract: Developing a vaccine for human immunodeficiency virus (HIV) may be aided by a complete understanding of those rare cases in which some HIV-infected individuals control replication of the virus. Most of these elite controllers express the histocompatibility alleles HLA-B*57 or HLA-B*27 (ref. 3). These alleles remain by far the most robust associations with low concentrations of plasma virus, yet the mechanism of control in these individuals is not entirely clear. Here we vaccinate Indian rhesus macaques that express Mamu-B*08, an animal model for HLA-B*27-mediated elite control, with three Mamu-B*08-restricted CD8(+) T-cell epitopes, and demonstrate that these vaccinated animals control replication of the highly pathogenic clonal simian immunodeficiency virus (SIV) mac239 virus. High frequencies of CD8(+) T cells against these Vif and Nef epitopes in the blood, lymph nodes and colon were associated with viral control. Moreover, the frequency of the CD8(+) T-cell response against the Nef RL10 epitope (Nef amino acids 137-146) correlated significantly with reduced acute phase viraemia. Finally, two of the eight vaccinees lost control of viral replication in the chronic phase, concomitant with escape in all three targeted epitopes, further implicating these three CD8(+) T-cell responses in the control of viral replication. Our findings indicate that narrowly targeted vaccine-induced virus-specific CD8(+) T-cell responses can control replication of the AIDS virus.

Activities of the triazole derivative SCH 56592 (posaconazole) against drug-resistant strains of the protozoan parasite Trypanosoma (Schizotrypanum) cruzi in immunocompetent and immunosuppressed murine hosts.

Abstract: We have studied the in vivo activity of the new experimental triazole derivative SCH 56592 (posaconazole) against a variety of strains of the protozoan parasite Trypanosoma (Schizotrypanum) cruzi, the causative agent of Chagas' disease, in both immunocompetent and immunosuppressed murine hosts. The T. cruzi strains used in the study were previously characterized as susceptible (CL), partially resistant (Y), or highly resistant (Colombiana, SC-28, and VL-10) to the drugs currently in clinical use, nifurtimox and benznidazole. Furthermore, all strains are completely resistant to conventional antifungal azoles, such as ketoconazole. In the first study, acute infections with the CL, Y, and Colombiana strains in both normal and cyclophosphamide-immunosuppressed mice were treated orally, starting 4 days postinfection (p.i.), for 20 consecutive daily doses. The results indicated that in immunocompetent animals SCH 56592 at 20 mg/kg of body weight/day provided protection (80 to 90%) against death caused by all strains, a level comparable or superior to that provided by the optimal dose of benznidazole (100 mg/kg/day). Evaluation of parasitological cure revealed that SCH 56592 was able to cure 90 to 100% of the surviving animals infected with the CL and Y strains and 50% of those which received the benznidazole- and nifurtimox-resistant Colombiana strain. Immunosuppression markedly reduced the mean survival time of untreated mice infected with any of the strains, but this was not observed for the groups which received SCH 56592 at 20 mg/kg/day or benznidazole at 100 mg/kg/day. However, the overall cure rates were higher for animals treated with SCH 56592 than among those treated with benznidazole. The results were confirmed in a second study, using the same model but a longer (43-dose) treatment period. Finally, a model for the chronic disease in which oral treatment was started 120 days p.i. and consisted of 20 daily consecutive doses was investigated. The results showed that SCH 56592 at 20 mg/kg/day was able to induce a statistically significant increase in survival of animals infected with all strains, while benznidazole at 100 mg/kg/day was able to increase survival only in animals infected with the Colombiana strain. Moreover, the triazole was able to induce parasitological cures in 50 to 60% of surviving animals, irrespective of the infecting strain, while no cures were obtained with benznidazole. Taken together, the results demonstrate that SCH 56592 has in vivo trypanocidal activity, even against T. cruzi strains naturally resistant to nitrofurans, nitroimidazoles, and conventional antifungal azoles, and that this activity is retained to a large extent in immunosuppressed hosts.

Prevalence, Awareness, Treatment and Influence of Socioeconomic Variables on Control of High Blood Pressure: Results of the ELSA-Brasil Study.

Abstract: High blood pressure (HBP) is the leading risk factor for years of life lost in Brazil. Factors associated with HBP awareness, treatment and control need to be understood better. Our aim is to estimate prevalence, awareness, and types of anti-hypertensive treatment and to investigate the association of HBP control with social position. Data of 15,103 (54% female) civil servants in six Brazilian state capitals collected at the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline (2008-2010) were used to estimate prevalence and cross-sectional association of HBP control with education, per capita family income and self-reported race, using multiple logistic regression. Blood pressure was measured by the oscillometric method. 35.8% were classified as presenting HBP; 76.8% of these used anti-hypertensive medication. Women were more aware than men (84.8% v. 75.8%) and more often using medication (83.1% v. 70.7%). Adjusted HBP prevalence was, in ascending order, Whites (30.3%), Browns (38.2%) and Blacks (49.3%). The therapeutic schemes most used were angiotensin-converting enzyme inhibitors, in isolation (12.4%) or combined with diuretics (13.3%). Among those in drug treatment, controlled blood pressure was more likely in the (postgraduate) higher education group than among participants with less than secondary school education (PR = 1.21; 95% CI: 1.14–1.28), and among Asian (PR = 1.21; 95% CI: 1.12–1.32) and ‘Whites (PR = 1.19; 95% CI: 1.12–1.26) compared to Blacks. Socioeconomic and racial inequality—as measured by different indicators—are strongly associated with HBP control, beyond the expected influence of health services access.

Global genetic diversity of Aedes aegypti

Abstract: Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae. aegypti from 30 countries in six continents, and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae. aegypti formosus and Ae. aegypti aegypti as genetically distinct units. Ae. aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co-occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya), the two subspecies remain genetically distinct, whereas in urban settings, they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats and low migration rates. Ancestral populations in sub-Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae. aegypti to the New World coinciding with trans-Atlantic shipping in the 16th to 18th centuries was followed by its introduction to Asia in the late 19th century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae. aegypti s.l. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae. aegypti, especially for the methods using genetic modification of populations.

Use of titanium dioxide photocatalysis on the remediation of model textile wastewaters containing azo dyes.

Abstract: The photocatalytic degradation of two commercial textile azo dyes, namely C.I Reactive Black 5 and C.I Reactive Red 239, has been studied. TiO2 P25 Degussa was used as catalyst and photodegradation was carried out in aqueous solution under artificial irradiation with a 125 W mercury vapor lamp. The effects of the amount of TiO2 used, UV-light irradiation time, pH of the solution under treatment, initial concentration of the azo dye and addition of different concentrations of hydrogen peroxide were investigated. The effect of the simultaneous photodegradation of the two azo dyes was also investigated and we observed that the degradation rates achieved in mono and bi-component systems were identical. The repeatability of photocatalytic activity of the photocatalyst was also tested. After five cycles of TiO2 reuse the rate of colour lost was still 77% of the initial rate. The degradation was followed monitoring the change of azo dye concentration by UV-Vis spectroscopy. Results show that the use of an efficient photocatalyst and the